GENUINE, spiritual mourning for sin is the work of the Spirit of God. Repentance is too choice a flower to grow in nature's garden. Pearls grow naturally in oysters, but penitence never shows itself in sinners except divine grace works it in them. If thou hast one particle of real hatred for sin, God must have given it thee, for human nature's thorns never produced a single fig. "That which is born of the flesh is flesh."
True repentance has a distinct reference to the Saviour. When we repent of sin, we must have one eye upon sin and another upon the cross, or it will be better still if we fix both our eyes upon Christ and see our transgressions only, in the light of His love.
True sorrow for sin is eminently practical. No man may say he hates sin, if he lives in it. Repentance makes us see the evil of sin, not merely as a theory, but experimentally—as a burnt child dreads fire. We shall be as much afraid of it, as a man who has lately been stopped and robbed is afraid of the thief upon the highway; and we shall shun it—shun it in everything—not in great things only, but in little things, as men shun little vipers as well as great snakes. True mourning for sin will make us very jealous over our tongue, lest it should say a wrong word; we shall be very watchful over our daily actions, lest in anything we offend, and each night we shall close the day with painful confessions of shortcoming, and each morning awaken with anxious prayers, that this day God would hold us up that we may not sin against Him.
Sincere repentance is continual. Believers repent until their dying day. This dropping well is not intermittent. Every other sorrow yields to time, but this dear sorrow grows with our growth, and it is so sweet a bitter, that we thank God we are permitted to enjoy and to suffer it until we enter our eternal rest.
C. H. Spurgeon